Tonneau cover



FIG. 1 is a top perspective view of a tonneau cover, showing my new design;

FIG. 2 is a partial cross-sectional view thereof, taken generally along lines 2-2 of FIG. 6;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a left-side elevational view thereof, the right-side elevational view being a mirror image thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines in FIGS. 3-5 and 7 illustrate environmental matter that forms no part of the claimed design. 

CLAIM I claim the ornamental design for a tonneau cover, as shown and described. 